Israeli Intelligence Minister Yisrael Katz on Tuesday welcomed the killing of a leading Syrian weapons scientist but declined to comment on reports his government was behind the fatal bombing.

General Aziz Asbar, head of a Syrian government weapons research centre, was killed along with his driver when the bomb hit his car on Saturday, the Britain-based Syrian Observatory for Human Rights said.

The pro-government Al-Watan newspaper confirmed the killing in the central province of Hama.

Asbar headed the Maysaf research centre in Hama, which was hit by Israeli air strikes last month and in September last year, the Observatory said.

The New York Times on Monday quoted "a senior official from a Middle Eastern intelligence agency" as saying that Israel was behind the assassination.

"We don't of course comment on reports of this kind and I'm not going to comment now," Katz told Israeli army radio.

"I can say that assuming the details of this man's activities are correct and he was engaged in developing chemical weapons and longer-range missiles capable of hitting Israel, I certainly welcome his demise."

An Israeli air strike targeted the research centre on July 22, Syrian state media and the Observatory reported. An Israeli military spokesman declined to comment.

A September 2017 strike caused damage to the centre, when fire broke out at a warehouse where missiles were being stored, the Observatory said.

Israel has carried out numerous strikes inside Syria since 2017, according to the Observatory, targeting government forces and their allies from Iran and Lebanese Shiite militant group Hezbollah.

Early 2017 marked the low point for Syrian President Bashar al-Assad in his country's now seven-year-old civil war with his authority confined to just 17 percent of national territory.

A succession of victories since then over both the Islamic State group and various rebel factions has extended government control to nearly two-thirds of the country.